PARIS - French President Nicolas Sarkozy promised massive investments in education, research and nuclear power on Monday, touting his economic record as a top rival entered the 2012 presidential race. As Sarkozy held a major news conference, the 2012 campaign heated up with the opposition Socialists declaring that their party leader Martine Aubry, 60, would announce her bid to win a presidential nomination on Tuesday. "If France wants to remain a great nation and preserve and finance its social model, it must invest massively: innovation, research, universities, health, digital, industry," Sarkozy told his news conference. His appearance was ostensibly aimed at reviewing his 35-billion-euro ($50-billion) "big loan" stimulus programme launched in 2009 to fight the economic crisis, but circumstances gave it a strong electoral flavour. Sarkozy has yet to formally announce a r...